Risk Analysis: The only risk involved is the extra amount of radiation required to obtained the floroscopically guided Xrays. As stated above the maximum amount of radiation is 3 rem which includes the radiation from the standard Xrays. According to published literature, exposure risks below 5-10 rem are minimal. Health effects have not been consistently demonstrated for radiation exposure below 10 rem. To protect the subjects a licensed radiology technologist (RT) employed by the hospital will perform the fluoroscopy procedures and the Xrays. Jeff Jarnagin PA or Edwin Spencer MD will be present at all times during the fluoroscopy procedure. Subjects will be provided proper shielding (lead apron) throughout the activities. The licensed radiology technologist at the hospital will have the final responsibility for providing proper shielding.